The effect of subinhibitory concentrations of monobactams on bactericidal activity of macrophages

Abstract

It has been demonstrated that subminimum inhibitory concentrations (sub-MICs) of antibiotics have some effects on bacterial growth rate and morphology [8]. In other studies, it has been shown that sub-MICs of antibiotics alter adhesiveness of bacteria to mucosal surfaces [4] and enhance the bactericidal activity of human polymorphonuclear-leukocytes [1,10,11]. In addition to chemotherapy, host-defence reactions are important to host resistance against microbial infection. It is not fully understood how sub-MICs of antibiotics influence interactions between bacteria and the human host. We have been studying the effect of sub-MICs of antibiotics on such interactions, and found that monobactams, monocyclic β-lactam antibiotics (Aztreonam and AMA1080) potentiate the bactericidal activity of macrophages. Thus, monobactams may be expected to be useful agents for the clinical treatment of bacterial infections.